Replies

1. 
   Virginbuild | Mar 27, 2006 05:54am | #1

   Simplest is replace with a HEPA filter. You should be able to find same size at a hardware or home center. They cost several times more than a woven glass filter. I used a washable HEPA filter for a while but the seals wore out after a few times.

   I like the electronic filters. I have those installed now. It will require some sheet metal work to install the frame "cabinet". Like with all filters, you must be religious with a cleaning schedule. Electronic filters will start emitting ozone when they get dirty and that is not a healthy situation. Also when they get dirty they will arc and sometimes cause a small fire with the dust that has collected. Keep them clean and they really work well.

   Regards,

   Virginbuild

1. 
   sungod | Apr 11, 2006 09:43pm | #2

   Forget Electronic air filters for you forced air system. The major problem is that the movement of air is just too fast. Dust will accumulate on the grids and then is blown off. Adding more filter grills, bigger filters, multiple filters, thick hepa filters all translate into more surface area with slower airflow, make better efficiency.

1. 
   Virginbuild | Apr 12, 2006 12:28am | #3

   Hi Sungod,

   Respectfully,

   The collected dust does not depart from the grids. Once it is attached to the grid cell it stays put by the same force that put it there in the first place. An extra heavy dust particle will even make a "cracking electrical discharge" as it to is attracted to the collector plate. If you should neglect to clean the cells they will cause an ionizing corona which produces ozone which is not healthy in large doses. I have installed and used electronic air cleaners for the past 40 years and I stand by their efficiency.

   The HEPA filter is also a good filter and if someone likes that type there is no reason to go with it. Like we would say in my sailing days, different ships different splices.

    

   Regards,

   Virginbuild

1. 
   sungod | Apr 12, 2006 06:08am | #6

   "Respectfully,The collected dust does not depart from the grids. Once it is attached to the grid cell it stays put by the same force that put it there in the first place. An extra heavy dust particle will even make a "cracking electrical discharge" as it to is attracted to the collector plate. If you should neglect to clean the cells they will cause an ionizing corona which produces ozone which is not healthy in large doses. I have installed and used electronic air cleaners for the past 40 years and I stand by their efficiency." Just place a filter after the electronic filter and see how much it catches. An Ionic Breeze in one room will catch more dirt in a week than ANY whole electronic filter. In the 1950's I built a Heathkit filter, there was 2 fan speeds, the slower speed catches more dust. The amount of air speed from a furnace WILL blow off any dirt, the grids will collect just a fine dust, but not one bit of lint. I know the electronic filter in my furnace is working, it snaps and collects fine dust, but a $2 filter will catch a hundred times more.

2. 
   SteveFFF | Apr 12, 2006 12:57am | #4

   We installed a Honeywell electronic filter in my last house for something over $600. During the monthly cleanings I removed a rather unimpressive amount of dirt. Granted I scored a huge pile of HEPA filters at an auction (the 3M ones that cost $13 - $14 each) so they got changed regularly and may been catching the lion's share but I don't think I would install another one.Steve.

2. 
   DanH | Apr 12, 2006 01:14am | #5

   It's kind of silly that you have to lay out $300 for what's essentially an empty box, but probably the best choice is one of the roughly 8-inch-thick media (paper) filter systems sold by Aprilaire and several others.

   This is basically like a regular corrugated paper filter, but it has about 8 times the surface area. This makes the rate of flow through a given square inch of the filter much lower, allowing a "tighter" filter without excessive pressure loss, and reducing the force of air that would otherwise force dust through the filter.

   An added bonus is that you only have to change the filter media once a year. The media is more expensive than normal disposables, of course, but not outrageously so.

   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
3. 
   Blueductman | Apr 12, 2006 04:03pm | #7

   You have 2 issues, will you do the monthly maintenance (cleaning or changing filters?or do you want something that you do once a year?

   1. You can get at the box stores many type of filters and many have described their uses in your reply's, any good (high Merv rating will work on a monthly change out basis.

   2. You can put in a bypass HEPA filter that are listed medical devices ( $900-$1000. installed, once a year a prefilter gets changed and once every three 3-years you cgange the HEPA filter.

   3. Check the condition of your coil, once it starts condencenong water (AC use) you start collecting mold on the coil which cuts down your energy  (btu) output, have your coil cleaned twice a year , start of heating season (get off the mold and gunt after AC season is over to keep it fairly clean through the heating season, then reclean in Spring to start the ac season clean, or installa UVC fixture at the coil and it will keep the coil clean all year-you change the bulb once a year, keeps systaem clean and at highest efficency (=lowest cost of use)

    Good Luck, Ken

1. 
   DanH | Apr 12, 2006 05:18pm | #8

   I've read this about cleaning the coil, but in most furnace/AC installations around here there's no way to do that, short of hacking a hole in the unit. Further, when we had our furnace replaced a couple of months back, they kept the old A coil (which was maybe 8 years old). I saw it while they had things apart and it didn't appear to need cleaning.
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

1. 
   Blueductman | Apr 20, 2006 07:12am | #9

   One of the interseting things is that most service contracts have or include coil cleaning as part of any recommedned annual service and yet many like yours are built right into the duct work. You should have them next time cut an access panel so that they can clean annually or inspect form physical condition annually to knoe if it needs cleaning or not. What you see on the outside fins may not look anything like the inside view, where the air enters the coil then pushes through.

   All coil cleaning products site the coils need cleaning because a two year old coil can start losing up to 20-30% of its efficiency of output Btu's due to the film created by condensation and the naturally occuring mold and bacteria growth that takes place on all coils with condensate on them. Also its been documentated many ways that a coil with UVC on it will operate at what ever its peak efficiency is due to its cleaning ability of an AC or Heat pump coil.

   Well good Luck, Ken H.

1. 
   DanH | Apr 20, 2006 01:41pm | #10

   But the UV lamp is on the outside, and you say it's the inside where the crud collects.
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison

1. 
   Blueductman | Apr 21, 2006 04:33pm | #11

   The UVC light reflectes its way through the coil, Flat fins light passes over, deflected fins =  light bounces fron one to the other as it pases through, you can se the light from the other side ,you can not see the emitter bulb though, be glad to discuss UVC worked with it now for 4 years,Ken H

2. 
   rjw | Apr 21, 2006 04:45pm | #12

   Interesting info

   From your forum name, am I right in "guessing" you're an HVAC guy?

   (If we call electricians "sparky," can we call you a .... ahhh, never mind <!---->)<!---->

   Fighting Ignorance since 1967

   It's taking way longer than we thought

1. 
   Blueductman | Apr 21, 2006 04:50pm | #13

   Thats what I like about us OHIO boys we get straight to the point, now guess what blue duct stands for,

1. 
   DanH | Apr 21, 2006 08:55pm | #14

   What, you never played "Duct, duct, blue duct" as a kid?
   If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison